DTC P1684: General Description
The electronic throttle control system controls the throttle valve opening. The system includes the throttle actuator, the throttle valve, throttle position (TP) sensors A and B, the PGM-FI subrelay circuit, the accelerator pedal position (APP) sensor A/B, and the powertrain control module (PCM). The throttle valve return spring is attached to the throttle valve gear to return the throttle valve to the default position. To confirm that the throttle valve is operating normally, and if the detecting condition meets, the throttle valve moves to a specified position and closes to the target position by the throttle valve return spring. If the throttle valve does not move to the target position range, the PCM detects a throttle valve return spring malfunction and stores a DTC.